Apparatus for the pneumatic separation of materials of different densities



March 4, 1933- P. SOULARY APPARATUS FOR THE PNEUMATIC SEPARATION OF MATERIALS OF DIFFERENT DENSITIES Filed Feb. 19, 1931!.

P Joue/ary Patented Mar. 14, 1933 @FFICE PAUL SOULABY, OF BRUAY-EN-ARTOIS, FRANCE APPARATUS FOR THE PNEUBLATIG SEPARATTON 01* MIATERIALS OF DIFFERENT DENSITIES Application filed February 19, 1931, Serial No. 517,091, and. in France February 26,1930.

This invention relates to apparatus used for the pneumatic separation of materials of different densities contained in a heterogeneous mixture such as mixtures of coal which are to be sorted according to different qualities or cate ories of fuels. The invention more particularly concerns the apparatus described in the United States Patent application filed on August 12, 1929, under Serial No. 385,132 in the name of the applicant.

This apparatus comprises a series of boxes disposed in cascade arrangement and which, receiving periodical shaking movements, sort, by order of densities, the heterogeneous materials which circulate in sheet form from one box to the other. The products of greatest density are collected to constitute a lower layer in the boxes, some of which are provided with drawing off or evacuation means for these various products.

The apparatus, although capable of receiving various applications, is more particularly intended to be used for sorting coal in the coal industry. But, if for the purpose of simplifying and rendering clearer the description of the improved means forming the subject-matter of the present invention, use is made of particular terms: coal, mixed coal, schist, instead of general terms, such as materials of low, medium and high density, it is to be understood that the scope of the invention is not thereby reduced and that the ran e of its applications is not limited.

In boxes provided with means for removing the schist, the output of the same is determined by the passage cross-section and the speed of flow. The section is determined by adjustment of a shutter, the position of which is so chosen that the height of this section be at least equal to the greatest dimension of the fragments of material to be evacuated. It may then happen, in these conditions, that the output be greater the. the quantity of schist it is necessary to evacuate.

The improvements forming the subjectmatter of the invention have for main object to remedy this inconvenience. They also relate, on the one hand, to means for retaining in the box the non-sorted products, whilst allowing the sorted products to pass freely towards their respective outlets, and, on the other hand, to means for allowing the control, during the operation of the apparatus, of the distribution'of the air blown under the perforated bottoms of the boxes.

For that purpose, the improvements forming the subject-matter of the present invention are characterized by the following points:

(a) The height of the outlet section of the dense products is controlled by a sill held stationary in a position allowing the passage of the largest fragments, and on the down side of which is arranged a damper acting as a weir for controlling, according to its position, the speed of flow of the products.

(1)) Transverse dams are arranged in the boxes and their height and positions are determined for retaining, between two upper and lower layers of respectively light and heavy products already sorted, an intermediate layer of non-stratified products, the stratified products freely passing over and below the fixed sill, the thickness of which, in the vertical direction, is adjusted by a movable wall terminating in a shutter.

Fixed partitions or deflectors are combined with the shutters for distributing the air blown under the boxes, in order to improve the distribution of this air through the layers of treated products.

The accompanying drawing illustrates, by way of example only, a diagrammatic section of a box provideo with the improvements such as above characterized.

According to the present invention, a shutter 52 of special sha as, provided with a lower cheek member 53 is movable in front of a sill L adjusted once for all in order to allow free passage of the largest pieces or fragments to be evacuated. As the outflow through such an orifice might be too great, an inclined damper 55, sliding in its own plane, indicated by the arrow 57, is adjusted, for instance by meansof asystem of levers 56, to a suitable level for obtaining, owing to the resistance thus created, the de sired outflow. As shown in the drawing, it is desirable that the perforated surface should be at a lower level than the inlet 58 for the products, and this for giving to the bed of treated materials a sufficient thickness, in order that the surface 59 for separating the pure schists from the mixed coal should be well above the sill 54, as illustrated.

Moreover, by operating the shutter 52, its upper edge 60 can be brought above the level 61, under which can be situated schists which are not yet sorted. In these conditions, the latter remain therefore subjected to the stratifying action of the apparatus until they have moved down to the level of the sill 54:. For completing this action, a series of dams 62 is transversely arranged in the box. These dams allow only the light and heavy products already stratified to progress rapidly towards their respective outlets. 011 the contrary, they retard the progression of the products not yet sorted and retain them in the apparatus until their sorting is effected. This allows,in case the coal treated does not contain real mixed products, of avoiding the re-circulation in the apparatus of the intermediate products. If, on the contrary, the coal contains real mixed products, the latter can be collected separately by means of a shutter 63. Finally, for allowing a perfect distribution of the air blown under the perforated surface 10, fixed partitions 64 are provided; these partitions 64 are completed by shutters 65 pivoting about a shaft 66, the setting of which can thus be adjusted dur ing the operation of the apparatus. Boxes of the type just described, can, of course, be grouped in series with a number of other boxes of any type used in the known apparatus.

What I claim as my invention and desire to secure by Letters Patent is:

1. In a box for an apparatus for pneumatically sorting materials of different densities and of the kind described, transverse partitions arranged in the box and the lower edge of which is at a certain level above the bottom of the said box for retaining a layer of nonsorted materials, a fixed sill at the end located on the down side of the box for providing an outlet of definite height above the bottom of the box, a transverse damper arranged on the down side of the said bottom, means for adjusting the height of the upper edge of the said damper above the said bottom, a damper movable in front of the said sill, a wall above the said sill for forming an extension of the said damper and movable with the latter for constituting an adjustable weir for the materials of the lowest density. an adjustable damper arranged above the down side portion of the said wall.

2. In a box for an apparatus for pneumatically sorting materials of different densities and of the kind described, a perforated bottom, transverse partitions arranged in the box and the lower edge of which is at a certain level above said bottom of the said box for retaining a layer of nonsorted materials, a fixed sill at the end located on the down side of the box for providing an outlet of definite height above said bottom, a transverse damper arranged on the down side of the said bottom, means for adjusting the height of the upper edge of the said damper above the said bottom, a damper movable in front of the said sill, a wall above the said sill for forming an extension of the said damper and movable with the latter for constituting an adjustable weir for the materials of the lowest density, an adjustable damper arranged above the down side portion of the said wall, partitions arranged below the perforated bottom of the box in the zone where air is blown in, and shutters arranged in the spaces between the said partitions for distributing the air blown under the perforated bottom of the box.

In testimony whereof I have signed this specification.

PAUL SOULARY. 

